Telemetry during safety mode operation

An implantable device comprising:

• a therapy circuit configured to provide a therapy to a subject according to a therapy mode, wherein the implantable device is configured to provide an audio indication of the therapy;
• a communication circuit configured to communicate with an external device via a telemetry link;
• a logic circuit communicatively coupled to the communication circuit;
• and
• a processor, communicatively coupled to the logic circuit and the communication circuit, wherein the processor is configured to communicate information with the external device, via the communication circuit and the logic circuit, using a set of communication messages, and
• wherein, while in a device safety mode entered in response to detecting an error of the implantable device, the processor is held in an inactive state and the logic circuit is configured to:
• detect a therapy control request message from the external device, wherein the therapy control request message indicates an action to be taken by the logic circuit;
• change the therapy mode of the implantable device according to the indicated action;
• disable the audio indication according to the indicated action;
• communicate with the external device using a subset of the set of communication messages.

A method comprising:

• communicating information via a telemetry link between a processor of an implantable device and an external device using a set of communication messages, wherein the implantable device is a cardiac function management (CFM) device that provides electrical therapy to a subject according to a therapy mode;
• inactivating the processor while the implantable device is in a device safety mode, wherein the device safety mode is entered in response to detecting an error of the implantable device;
• communicating information between the external device and a logic circuit of the implantable device using a subset of the set of communication messages while the implantable device is in the device safety mode, including communicating a message to change the therapy mode of the implantable device;
• and
• reducing functionality of the implantable device according to tiers of functionality while the implantable device is in the device safety mode, wherein a first tier of reduced functionality includes reduced therapy functionality and reduced communication functionality, and a second tier of reduced functionality includes no communication functionality.

A system comprising:

• an implantable cardiac function management (CFM) device and an external device to communicate with the implantable CFM device, wherein the implantable CFM device includes:
• a therapy circuit configured to provide a therapy to a subject according to a therapy mode;
• a communication circuit configured to communicate via a telemetry link with an external device;
• a logic circuit communicatively coupled to the communication circuit;
• and
• a processor, communicatively coupled to the logic circuit and the communication circuit, wherein the processor is configured to communicate information with the external device, via the communication circuit and the logic circuit, using a set of communication messages, and
• wherein, while in a device safety mode entered in response to detecting an error of the implantable device, the processor is held in an inactive state and the logic circuit is configured to communicate with the external device using a subset of the set of communication messages, including a message to change the therapy mode of the implantable device;
• and
• reduce functionality of the implantable device according to tiers of functionality, wherein a first tier of reduced functionality includes reduced therapy functionality and reduced communication functionality, and a second tier of reduced functionality includes no communication functionality.